General

Nodemaks can be seen as classification-tags in OpenSceneGraph. Every Node in a file has a Nodemask. Usually this is the default mask, specified in the OSG Exporter-options dialog, but special ones can be used as well, using the Nodemask Helper.

Possible uses:

You can use the Helper to specifically designate parts of your scene as blocked, using a Collision Mask

Or explicitly let an object be walked through (using a no-collision mask).

To create a Nodemask Helper in 3d Studio Max

Create some geometry;

Add an OSG Nodemask Helper object to your scene;

Using the 'Add' of 'Add multiple'-butons add the geometry to the Helper;